Not sure if this has been mentioned, but what about John Henson from the Bucks?
He can play PF and C, and has excellent size. Good shot blocker and rebounder. Could be a nice fit next to Cousins. Still on his rookie deal as well.
Granted their interest would be dependant on what line up they go with (ie Knight, Mayo, Giannis, Parker, Sanders or Knight, Giannis, Parker, Ilyasova or Henson, Sanders etc), and if they decide to keep Ersan Ilyasova, but Henson could be an excellent acquisition if we could pull a deal off for him.
Obviously Sanders could be an option as well, but a guy like Henson does come without negative track record (?).